To provide a material supply device for an injection molding machine which is capable of easily adjusting the phase among a plurality of screws in the assembly and adjustment and easy in the restoration of the phase among the supply screws after disassembly.

The material supply device for the injection molding machine is provided with; a first and a second supply screw 12a, 12b connected to each of a power shaft 26a, 26b provided with a gear 28a, 28b connected to a motor 30 through each of a connection member 24a, 24b and having a structure having a spiral groove so that a screw groove 16a and a screw groove 16b mutually face the opposed direction; a screw flight 14a, 14b arranged to be pushed out to an opponent screw groove 16a, 16b and provided to set two screw flights side by side so that each of the rotary axis is in parallel in a material supply device body 10; and a connection member 24a, 24b provided with a phase matching part to match the phase to and connected to the supply screw or the power shaft at one end and a connection part capable of connecting the power shaft or the supply screw to the phase in a free position at another end.